Mercury 4hp 2 stroke, help please

[bantsam]

Hi all, Sam here from England, new to site and I'm looking for some help please. I have just bought a second hand 4 hp OBM. It didn't come with a manual so I need some info, I believe its a 1990 model but i'm not sure. The chap I bought it from said it was 100 to 1 mix, I think it should be 50 to 1, advice please. Its running a bit rough and I would like to service it but would need to have the correct manual and know what model it is for parts. Serial no is 09607146 and was made in Belgium. Cheers Sam

 

[carholme]

Re: Mercury 4hp 2 stroke, help please

Sam;

That s/n comes up as:

4 4 (Japan) 1-cyl 9586000 9629999 1990 Belgium

From here:

http://www.marinshopen.se/Motorer/O.../Mercury2takt1cyl225hp/tabid/479/Default.aspx

Parts Listing:

http://www.crowleymarine.com/mercury-outboard/340.cfm

Service Manual P/N: 90-17308R02

http://www.ebay.com/itm/Mercury-Marine-4-5-102cc-Sailpower-outboard-manual-90-17308R02-/220930229819

Gerry

 

[bantsam]

Re: Mercury 4hp 2 stroke, help please

Cheers Gerry, that was quick, much appreciated.

 

[mercuk]

Re: Mercury 4hp 2 stroke, help please

Sam I'm from uk as well...
Where abouts are you I might be able to help out if your local...

 

[bantsam]

Re: Mercury 4hp 2 stroke, help please

Hi, I'm in Tamworth, Staffs.

 

[mercuk]

Re: Mercury 4hp 2 stroke, help please

Hi, I'm in Tamworth, Staffs.

Ahh no go then matey, I'm in dorset...

 

[bantsam]

Re: Mercury 4hp 2 stroke, help please

Thanks anyway, perhaps I could pick your brains through the forum. What mix would you recommend ? I changed the fuel in the tank to 50 to 1. It starts fine and will idle but it won't increase when in gear. It has also raced away out of gear without using the throttle, could this be the carb. I have just ordered a manual so I hope I will get the answers there.

Cheers Sam

 

[mercuk]

Re: Mercury 4hp 2 stroke, help please

Thanks anyway, perhaps I could pick your brains through the forum. What mix would you recommend ? I changed the fuel in the tank to 50 to 1. It starts fine and will idle but it won't increase when in gear. It has also raced away out of gear without using the throttle, could this be the carb. I have just ordered a manual so I hope I will get the answers there.

Cheers Sam

Sam, I would almost defo say carb problem by the sounds of it...
The engine block is a yamaha one and I know some of them did run on 100:1 mix. When you try to accelerate does it just bog down and die or does it just not increase in rpms much?!!

 

[bantsam]

Re: Mercury 4hp 2 stroke, help please

Hi, when in gear the engines starts to die, throttle back saves it from stalling. On the initial start up when I got it, it ran at idle put into gear and it would stop, even after the engine had warmed up. I replaced the fuel with fresh petrol and there was a slight improvement. It will now run in gear at low revs , increasing the throttle causes it to die.
Cheers Sam

 

[bantsam]

Re: Mercury 4hp 2 stroke, help please

Hi all, took carb apart and gave it a clean all is well now and motor runs a treat. Cheers